1. Field of Invention
This invention relates generally to the humidification of fibers, specifically cotton fibers in the form of lint, after the cleaning process and prior to the baling of cotton fibers, particularly to humidification of the cotton fibers by warm moist air under controlled conditions.
2. Description of Prior Art
For years the desirability of humidifying cotton prior to a baling process at cotton gins has been recognized, and many attempts have been made to accomplish this end. There are several reasons for humidifying cotton. Dry cotton is more difficult to press into a bale, it requires 66% more ram pressure to press a dry bale. After baling, dry cotton often breaks the steel wire strapping which contain the bale, necessitating additional labor to repress and replace such broken strapping. Cotton fibers absorb dye in the dyeing process in spinning mills if the moisture content is high.
The first known systematic method of humidifying cotton ahead of the baling press in a cotton gin was that of spraying the batt of cotton with a fine mist of water to which a wetting agent had been added. This method was developed by the U.S. Government's Cotton Ginning Laboratory at Stoneville, Miss.
In recent years, humid air has been applied in the battery condenser of a cotton gin just ahead of the doffing rollers. For example, U.S. Pat. No. 05,381,587 issued Jan. 17, 1995 to A. L. Vandergiff, this patent adds moisture in the battery condenser. The aforementioned apparatus adds moisture in the condenser but has an inherent problem of not being able to add enough moisture and causing expensive repairs to the condenser when moisture collects on the condenser screen. Heat has been added to the screen of the condenser, but with very little results. The aforementioned patent is extremely costly to purchase and has too many moving parts. There is a U.S. Pat. No. 4,103,397 issued Aug. 1, 1978 to S. G. Jackson which employes a tubular grid assembly for adding moisture to cotton fiber at the lint slide. This system is designed for very low capacity cotton gin plants and works marginal at best. All of the aforementioned apparatus are expensive to operate and account for a lot of down time. In U.S. Pat. No. 2,019,079 by Clyde Herring issued Oct. 29, 1935 a system is employed to prevent static electric from forming in cotton fibers while the cotton seed is still within the lint. There is one major problem with this application, when moist air is used in conjunction with machinery designed to clean cotton, there is the inherent nature of the machinery to condense back into water causing major problem with choke ups and down time on the machinery. U.S. Pat. No. 2,312,557 by R. M. Joyce issued Mar. 2, 1943 employes a method for establishing moisture content of fiber by means of injecting moist air directly into the end of the conveying flue, this application has major problems, there is no mention of controlling the problem of moist build up inside of the lint flue. When moist air is applied to a flue and no means to control the flue wall temperature, condensation is a huge problem. This build up will turn loose and choke the battery condenser. With this problem there is loss of production and undue machinery repairs. U.S. Pat. No. 2,747,234 by C. C. Speaks and A. C. Griffin, Jr. dated May 1956 is a planned control system whereby moisture content may be brought up to appropriate levels by adding moist air to machinery that was designated to do another job. With this system, one would have great problems controlling moisture and undue repairs on machinery due to moisture being added. U.S. Patent No. 2,867,851 by O. Mitchell issued Jan. 13, 1959 employes a method to add moisture to seed cotton prior to the seed and lint fiber being separate. This method will cause problems with the gin stand feeder in as much as the feeder has not had time to remove trash from the seed cotton, prior to moisture being added to the fiber. U.S. Pat. No. 3,881,222 by J. H. Roberson issued May 6, 1975 and U.S. Pat. No. 4,074,546 issued Feb. 21, 1978 employes the same method of spraying water and chemicals on raw fibers, as stated before this is just a get by method at best. One cannot expect to spray water on fibers and have the moisture penetration. Both would cause wet spots in cotton fibers along with wetting of machinery. U.S. Pat. No. 4,021,887 by S. G. Jackson issued May 10, 1977 has to do with the control aspect of a cotton gin, again this patent makes no mention of any method to accomplish the end means. File T975,001 dated Oct. 3, 1978 by G. J. Mangialardi, Jr. and A. C. Griffin, Jr. employes a method for handling seed cotton by means of a series of offset belts, this presents a few problems, one is how to control such an apparatus and another is how to justify the cost of such a device. There are inherent problems with belt conveying systems, the largest being the belt will get damp causing the fiber to stick to the belt which will cause choke ups and down time. U.S. Pat. No. 4,140,503 by A. L. vandergriff issued Feb. 20, 1979 uses a battery condenser to add moisture to cotton. This prior art has two large problems, one being the inability to control condensation and the other being limited exposure time to moisture. When moist air is applied to cold steel, moisture forms in the state of condensation resulting in choke ups and down time. U.S. Pat. No. 4,253,215 by G. J. Mangialardi, Jr. is a control schematic to allow the control of cotton flow into a lint cleaner. There is no mention of any moisture being added or the control of any such device. U.S. Pat. No. 4,253,243 by P. L. Whelan dated Mar. 3, 1981 employes a control method of sensing moisture and controlling a hot air supply. This patent does not mention anything about adding moisture to cotton fibers. U.S. Pat. No. 4,726,096 by c. Woods, Jr. issued Feb. 23, 1988 employes yet another method of praying water onto cotton fibers prior to the baling process, that method is a method that has several drawbacks to its use one being water will run off of cotton in its raw state, another being water will run down the lint slide causing cotton to stick to the metal and yet another is the inability to obtain enough moisture from this system. U.S. Pat. No. 4,862,559 dated Sep. 5, 1989 and U.S. Pat. No. 4,667,373 dated May 26, 1987 by E. A. Roder and G. J. Napper use live steam to inject into the bale of fiber while the fiber is located in the press to bring the level of moisture up in a given fiber. This system is very slow and one cannot get the moisture level up in cotton fibers due to the density of cotton fibers after the baling process. This prior art also mentions the use of high pressure steam in the process, this would cause a safety problem with special license and special insurance requirements deeming this application undesirable. U.S. Pat. No. 4,943,300 by L. Vinnikov dated Jul. 24, 1990 sets forth a mathematical formula for time exposure of cotton fiber to moist air in order to achieve a predetermined level of moisture, but makes no mention of how to achieve this end. All of the aforementioned apparatus are expensive to operate and account for a lot of down time. The end results are the same, when operating cost exceed results, operators will shut down their moisture systems due to high maintenance cost, down time and low absorption of moisture in the cotton fibers.
All of the aforementioned apparatus have been based on the same process of applying moisture to one side of the lint batt and hoped that it would penetrate throughout the batt, but this does not happen.
The problem with the aforementioned patents is that each one tried to add moisture to lint fiber after all lint was combined into a batt near the final process of the gin plant.
All of the aforementioned patents were state of the art at the time, but with the advancement of high capacity gin plants, state of the art controls and a more advanced understanding of cotton fibers and their need for moisture, there is a need for a new method of applying moisture to cotton fibers.